Thyroid cancer test helps patients avoiding unnecessary surgery

May 17, 2013

Dr. Sol Guerrero, endocrinologist at The Iowa Clinic, shows a test kit used to diagnose patients with thyroid cancer, which has been available at The Iowa Clinic for two months. / Mary Chind/The Register

Written by

Estela Villanueva-Whitman

Special to The Register

A new testing tool at The Iowa Clinic is helping better diagnose thyroid cancer and allowing some patients to avoid unnecessary surgery.

Cancer of the thyroid, a gland at the base of the neck, is diagnosed through a fine needle aspiration biopsy. In 15 to 30 percent of cases, results are inconclusive.

“This is where we’re making a difference,” explained Dr. Sol Guerrero, an endocrinologist at The Iowa Clinic, which according to manufacturer Veracyte, is the first practice in Iowa to offer Afirma thyroid FNA analysis.

Patients with such findings traditionally have been sent to surgery for proper diagnosis. However, about 70 to 80 percent of those surgeries show benign conditions.

“Most of these would turn out to be benign, but you would have had to do a surgery, which increases cost and risk for the patient. If you can have something that can give you the same outcome without doing surgery, then that’s what’s beneficial to the patient,” Guerrero said.

Surgical risks include nerve injury or infections, but may also result in hypothyroidism, causing patients to be on medication the rest of their lives.

Afirma offers additional testing through a gene expression classifier to give a more accurate diagnosis in such cases.

Guerrero saw positive results with the testing in Florida, where she worked before coming to Des Moines last year. The Iowa Clinic has used Afirma for about two months.

According to the American Cancer Society, thyroid cancer is the fastest-growing cancer in the U.S., with 60,220 new cases expected in 2013. Additional testing may explain the increase, Guerrero said. Often times the cancer is caught during tests or imaging for other conditions.

Thyroid nodules are common in the general population, Guerrero said. Patients may feel a lump or tenderness in the neck and have difficulty swallowing. Unless the nodule is large, it is usually found through a physical exam. Cancer is present in only about five percent of nodules, she noted.

Physicians may order a biopsy if nodules are greater than one centimeter in size. About 450,000 such tests are done annually in the U.S.

Before the new test was available, endocrinologists at The Iowa Clinic sent cells to be analyzed at Iowa Methodist Medical Center’s pathology lab. Collection kits are now sent to Texas to be analyzed by cytopathologists who specialize in thyroid cancer. Initial results are completed within 48 hours.

Patients whose results are benign continue to be monitored and return for an ultrasound in one year to see if nodules have changed.

Indeterminate findings go through additional gene expression testing and surgery is recommended only for patients with positive results.

A few patients at The Iowa Clinic have already benefited from the test. Maxwell Blend, 21, of Des Moines, learned he had an elevated thyroid level through blood work completed for a pre-existing stomach condition. An ultrasound showed a thyroid nodule, and testing through the new procedure came back indeterminate.

“It definitely worried me. It was an extra 10-day wait until I found out. Having that hang over your head for almost half a month makes it pretty rough,” said Blend, adding that he would have been set to start finals at the time if he had not taken the past semester off from college.

Learning the results were negative and that he avoided unnecessary surgery was a tremendous relief, Blend said. He’ll continue to have ultrasounds to monitor the nodule.

The thyroid analysis, along with the gene expression classifier, became available to physicians in January 2011. It’s been a significant advancement for the field, Guerrero said.

“I think it’s a great tool for patients to have access to because if this is something that can give them assurance without going through an unnecessary surgery, and our main focus should be on the best patient care we can provide, then that’s something they should be aware of,” she said.